One of a set of seven Admiralty (Hydrographic Office) chronometer issue cards giving place of issue and date. These thin paper cards were designed to slide into a brass frame inside the chronometer or deck watch box, and were to record the date at which the instrument was last issued from the Department responsible for servicing them. :

1939: Royal Observatory, Greenwich

1943: ‘H.M. Chronometer Depot’, Bradford on Avon (moved from Bristol about 1940)

1963: (by now shown as 'Form 213') ‘Chronometer Department’, Royal Greenwich Observatory, Herstmonceux Castle, Sussex

1965: ‘Chronometer Branch’, Hydrographer of the Navy, Herstmonceux Castle, Sussex

1975: ‘Chronometer Section’ Hydrographic Department, Ministry of Defence, Herstmonceux Castle, Hailsham, Sussex

The Chronometer Section officially closed in 1985.